关于arraylist的问题

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

request.setAttribute("score", 59);

request.setAttribute("grade", "D");

List list=new ArrayList();

// ArrayList list=new ArrayList();

list.add(new Company("腾讯", "www.tencent.com"));

list.add(new Company("百度", "www.baidu.com"));

list.add(new Company("muke", "www.imooc.com"));

request.setAttribute("companies", list);

request.getRequestDispatcher("/core.jsp").forward(request,response);

}

如果list的构造函数是new ArrayList(),我的eclipse会报错这是什么问题呢